Email Setup Wizard

Fastmail + DreamHost

Set up Fastmail email on DreamHost

The records Fastmail needs, written with the field names DreamHost uses (Host, Custom MX Records, TXT Value, Points to), in the order to add them.

  • 4 steps
  • 7 DNS records
  • Sources checked October 21, 2026

Before you start

  1. Have your Fastmail account ready. Some values are unique to your account and come from the Fastmail Settings.
  2. Open DNS at DreamHost: In the DreamHost panel, go to Manage Websites. Select the three-dot button under your domain, then DNS Settings.
  3. Keep both tabs open and add the records below one at a time.

Records to add

Copy each value with the button next to it. Rows marked “Copy from Fastmail Settings” are unique to your account.

MX records Where incoming email goes Type MX Host Leave empty Value 10 in1-smtp.messagingengine.com Priority in the value TTL Default
MX records Where incoming email goes Type MX Host Leave empty Value 20 in2-smtp.messagingengine.com Priority in the value TTL Default
SPF record Which servers may send as you Type TXT Host Leave empty Value v=spf1 include:spf.messagingengine.com ?all Priority n/a TTL Default
DKIM A signature on every message Type CNAME Host fm1._domainkey Value fm1.yourdomain.com.dkim.fmhosted.com Priority n/a TTL Default
DKIM A signature on every message Type CNAME Host fm2._domainkey Value fm2.yourdomain.com.dkim.fmhosted.com Priority n/a TTL Default
DKIM A signature on every message Type CNAME Host fm3._domainkey Value fm3.yourdomain.com.dkim.fmhosted.com Priority n/a TTL Default
DMARC record What to do with fakes · recommended Type TXT Host _dmarc Value v=DMARC1; p=none; Priority n/a TTL Default

Step by step in DreamHost

Point your MX records

MX records tell every other mail server where to deliver email for your domain. They must point to your provider and nowhere else.

Type
MX
Host
Leave this field empty
Custom MX Records
10 in1-smtp.messagingengine.com
Type
MX
Host
Leave this field empty
Custom MX Records
20 in2-smtp.messagingengine.com

In DreamHost

  1. Open the Custom MX page in the panel and click Edit to the right of your domain.
  2. In Custom MX Records, enter each record as the priority, a space, then the server (for example 1 ASPMX.GOOGLE.COM). Don't add @ or a final dot.
  3. Click Change this domain to use custom MX records now!
  4. Repeat for each MX record above.

Add the SPF record

SPF is a TXT record that lists the services allowed to send email from your domain, so receivers can spot forgeries.

Type
TXT
Host
Leave this field empty
TXT Value
v=spf1 include:spf.messagingengine.com ?all
  • This is the exact value from Fastmail's manual DNS guide, which ends in ?all (neutral).

In DreamHost

  1. On the DNS Settings page, click Add Record.
  2. Hover over the TXT section and click ADD.
  3. Fill in Host (leave it blank for your bare domain) and TXT Value.
  4. Click Add Record to save.

Set up DKIM

DKIM publishes a public key so receivers can confirm your messages really came from you and were not changed on the way.

Type
CNAME
Host
fm1._domainkey
Points to
fm1.yourdomain.com.dkim.fmhosted.com
Type
CNAME
Host
fm2._domainkey
Points to
fm2.yourdomain.com.dkim.fmhosted.com
Type
CNAME
Host
fm3._domainkey
Points to
fm3.yourdomain.com.dkim.fmhosted.com

In DreamHost

  1. On the DNS Settings page, click Add Record.
  2. Hover over the CNAME section and click ADD.
  3. Fill in Host (a subdomain, never the root) and Points to.
  4. Click Add Record to save.
  5. Repeat for each CNAME record above.

Add the DMARC record (recommended)

DMARC tells receivers what to do with mail that fails SPF and DKIM, and where to send reports about it.

Type
TXT
Host
_dmarc
TXT Value
v=DMARC1; p=none;

In DreamHost

  1. On the DNS Settings page, click Add Record.
  2. Hover over the TXT section and click ADD.
  3. Fill in Host (leave it blank for your bare domain) and TXT Value.
  4. Click Add Record to save.

Check your setup

Once the records are saved, run a live check. We look up your domain in public DNS and tell you what is right, missing or wrong, with the fix in DreamHost’s words.

We only read public DNS records. Nothing is stored.

Common mistakes with Fastmail on DreamHost

Adding fewer than three DKIM records

Fastmail signs with three selectors (fm1, fm2, fm3). All three CNAMEs are required.

Adding a second SPF record

Only one record may start with v=spf1. Merge Fastmail's include into the existing one.

DreamHost: Custom MX turns off DreamHost email

Once custom MX records are added, email is no longer delivered to DreamHost and the domain's DreamHost mailboxes are deactivated.

Visit Fastmail Visit DreamHost

Rather have someone do it for you?

Tell us your domain and we will add and verify every record for Fastmail on DreamHost, then send you the check results.

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Fastmail on DreamHost: questions

Where do I add Fastmail DNS records in DreamHost?

In the DreamHost panel, go to Manage Websites. Select the three-dot button under your domain, then DNS Settings. Add each record there, one at a time.

What goes in the Host field at DreamHost?

Leave it empty for records on your bare domain, such as MX and SPF. For the others, enter only the part before your domain, for example fm1._domainkey. DreamHost adds your domain automatically.

Do I need to delete my existing MX records at DreamHost?

Yes. Mail servers deliver to every MX record you publish, so keep only the Fastmail MX records and delete the rest. Once custom MX records are added, email is no longer delivered to DreamHost and the domain's DreamHost mailboxes are deactivated.

Where do I get my Fastmail DKIM record?

Fastmail DKIM records are CNAME records whose value includes your domain, for example fm1.yourdomain.com.dkim.fmhosted.com. Copy the exact values for your domain from the table on this page.

How long until Fastmail email works on DreamHost?

DreamHost says DNS updates can take several hours to fully update online.

Sources

Every value and step on this page comes from these official pages. Dashboards change, so if something doesn’t match what you see, tell us.

Fastmail on other hosts

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